Geothermal energy in sedimentary basins: What we can learn from regional numerical models

Abstract. In this contribution we present a review of scientific research results that address seismo-hydro-mechanical coupled processes relevant for the development of a sustainable heat exchanger in low permeability crystalline rock and introduce the design of the In-situ Stimulation and Circulation (ISC) experiment at the Grimsel Test Site dedicated to study such processes under controlled conditions. The review shows that research on reservoir stimulation for deep geothermal energy exploitation has been largely based on laboratory observations, large-scale projects and numerical models. Observations of full-scale reservoir stimulations have yielded important results. However, the limited access to the reservoir and limitations in the control on the experimental conditions during deep reservoir stimulations is insufficient to resolve the details of the hydro-mechanical processes that would enhance process understanding in a way that aids future stimulation design. Small scale laboratory experiments provide a fundamental insights into various processes relevant for enhanced geothermal energy, but suffer from 1) difficulties and uncertainties in upscaling the results to the field-scale and 2) relatively homogeneous material and stress conditions that lead to an over-simplistic fracture flow and/or hydraulic fracture propagation behaviour that is not representative for a heterogeneous reservoir. Thus, there is a need for intermediate-scale hydraulic stimulation experiments with high experimental control that bridge the various scales, and for which access to the target rock mass with a comprehensive monitoring system is possible. Only few intermediate-scale hydro-shearing and hydro-fracturing experiments have recently been performed in a densely instrumented rock mass. No such measurements have been performed on faults in crystalline basement rocks. The In-situ Stimulation and Circulation (ISC) experiment currently performed in a naturally fractured and faulted crystalline rock mass at the Grimsel Test Site (Switzerland) is designed to address open research questions, which could not be investigated in the required detail so far. Two hydraulic injection phases were executed to enhance the permeability of the rock mass: a hydro-shearing phase and then a hydraulic fracturing phase. During the injection phases the rock mass deformation across fractures and within intact rock, the pore pressure distribution and propagation and the micro-seismic response were monitored at a high spatial and temporal resolution.

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Formation conditions and evolution of oil and gas source strata of the Laptev sea shelf ore and gas province

Proceedings of higher educational establishments Geology and Exploration ◽

10.32454/0016-7762-2020-63-3-46-59 ◽

2021 ◽

pp. 46-59

Author(s):

V. Yu. Kerimov ◽

Yu. V. Shcherbina ◽

A. A. Ivanov

Keyword(s):

Oil And Gas ◽

Numerical Models ◽

Sedimentary Basins ◽

Water Area ◽

Source Rocks ◽

Gas Content ◽

Laptev Sea ◽

Hydrocarbon Generation ◽

Gas Source ◽

The Laptev Sea

Introduction. To date, no unified well-established concepts have been developed regarding the oil and gas geological zoning of the Laptev Sea shelf, as well as other seas of the Eastern Arctic. Different groups of researchers define this region either as an independently promising oil and gas region [7, 8], or as a potential oil and gas basin [1].Aim. To construct spatio-temporal digital models of sedimentary basins and hydrocarbon systems for the main horizons of oil and gas source rocks. A detailed analysis of information on oil and gas content, the gas chemical study of sediments, the characteristics of the component composition and thermal regime of the Laptev sea shelf water area raises the question on the conditions for the formation and evolution of oil and gas source strata within the studied promising oil and gas province. The conducted research made it possible to study the regional trends in oil and gas content, the features of the sedimentary cover formation and the development of hydrocarbon systems in the area under study.Materials and methods. The materials of production reports obtained for individual large objects in the water area were the source of initial information. The basin analysis was based on a model developed by Equinor specialists (Somme et al., 2018) [14—17], covering the time period from the Triassic to Paleogene inclusive and taking into account the plate-tectonic reconstructions. The resulting model included four main sedimentary complexes: pre-Aptian, Apt-Upper Cretaceous, Paleogene, and Neogene-Quaternary.Results. The calculation of numerical models was carried out in two versions with different types of kerogen from the oil and gas source strata corresponding to humic and sapropel organic matter. The results obtained indicated that the key factor controlling the development of hydrocarbon systems was the sinking rate of the basins and the thickness of formed overburden complexes, as well as the geothermal field of the Laptev Sea.Conclusion. The analysis of the results obtained allowed the most promising research objects to be identified. The main foci of hydrocarbon generation in the Paleogene and Neogene complexes and the areas of the most probable accumulation were determined. Significant hydrocarbon potential is expected in the Paleogene clinoforms of the Eastern Arctic.

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Analytical and Numerical Models for Determining Geothermal Energy Potential: A Case Study in India

Journal of Fundamentals of Renewable Energy and Applications ◽

10.4303/jfrea/r120309 ◽

2012 ◽

Vol 2 ◽

pp. 1-5

Author(s):

Michele De Carli ◽

Mirco Donà ◽

Antonio Galgaro ◽

Gúdni A. Jóhannesson ◽

Sergio Marinetti ◽

...

Keyword(s):

Geothermal Energy ◽

Numerical Models ◽

Energy Potential

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Stratigraphy of Architectural Elements of a Buried Monogenetic Volcanic System

Open Geosciences ◽

10.1515/geo-2019-0048 ◽

2019 ◽

Vol 11 (1) ◽

pp. 581-616 ◽

Cited By ~ 6

Author(s):

Alan Bischoff ◽

Andrew Nicol ◽

Jim Cole ◽

Darren Gravley

Keyword(s):

Geothermal Energy ◽

Sedimentary Basin ◽

Sedimentary Basins ◽

Volcanic Field ◽

Plumbing System ◽

Volcanic System ◽

Architectural Elements ◽

Stratigraphic Framework ◽

Cone Type ◽

Geological Evolution

Abstract Large volumes of magma emplaced and deposited within sedimentary basins can have an impact on the architecture and geological evolution of these basins. Over the last decade, continuous improvement in techniques such as seismic volcano-stratigraphy and 3D visualisation of igneous bodies has helped increase knowledge about the architecture of volcanic systems buried in sedimentary basins. Here, we present the complete architecture of the Maahunui Volcanic System (MVS), a middle Miocene monogenetic volcanic field now buried in the offshore Canterbury Basin, South Island of New Zealand. We show the location, geometry, size, and stratigraphic relationships between 25 main intrusive, extrusive and sedimentary architectural elements, in a comprehensive volcano-stratigraphic framework that explains the evolution of the MVS from emplacement to complete burial in the host sedimentary basin. Understanding the relationships between these diverse architectural elements allows us to reconstruct the complete architecture of the MVS, including its shallow (<3 km) plumbing system, the morphology of the volcanoes, and their impact in the host sedimentary basin during their burial. The plumbing system of the MVS comprises saucer-shaped sills, dikes and sill swarms, minor stocks and laccoliths, and pre-eruptive strata deformed by intrusions. The eruptive and associated sedimentary architectural elements define the morphology of volcanoes in the MVS, which comprise deep-water equivalents of crater and cone-type volcanoes. After volcanism ceased, the process of degradation and burial of volcanic edifices formed sedimentary architectural elements such as inter-cone plains, epiclastic plumes, and canyons. Insights from the architecture of the MVS can be used to explore for natural resources such as hydrocarbons, geothermal energy and minerals in buried and active volcanic systems elsewhere.

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Feedbacks between internal fluvial drainage and high-plateau tectonic growth. A mechanistic perspective.

10.5194/egusphere-egu2020-17481 ◽

2020 ◽

Author(s):

Daniel Garcia-Castellanos ◽

Weiming Liu ◽

Zhongping Lai ◽

Ivone Jiménez-Munt ◽

Lucía Struth ◽

...

Keyword(s):

Numerical Modeling ◽

Numerical Models ◽

Plate Boundary ◽

Active Regions ◽

Sedimentary Basins ◽

Tectonic Deformation ◽

The Tibetan Plateau ◽

Internal Drainage ◽

High Plateau ◽

River Incision

High-plateaus are relatively flat areas at high elevations. The stream-power river-incision law predicts that surface water incises the landscape proportionally to local river slope, and therefore the margins of high-plateaus are prone to a river erosion that should terminate the low relief of the highlands that characterizes the plateau. This means that long-lived high-plateaus need an additional mechanism to compete with river incision.In absence of tectonic deformation, river networks propagate into the plateau via a retrogressive wave of river incision. A well-constrained non-tectonic scenario is provided by the Neogene Duero and Ebro sedimentary basins in N Iberia, where ongoing incision rates presently range from .02 (Duero) to .5 m/kyr (Ebro) and have propagated upstream at similar rates of up to 0.2 km/kyr, based on cosmogenic dating studies combined with numerical modeling. These rates started with the transition from internal (endorheic) to external (exorheic) drainage of both basins sometime between 8 and 12 million years ago. Interestingly, while the pre-exorheic Ebro Basin sedimentary plateau has been mostly obliterated by erosion, the Duero Basin still preserves large areas of low relief, in spite of the very similar geological setting. The causes will be discussed using landscape evolution numerical modeling.In contrast, tectonically active regions can counteract river incision and preserve high plateaus by longer time periods. Recent studies based on sedimentary stratigraphy of endorheic basins suggest that large areas of the Tibetan high plateau remain internally drained since ca 35 Ma. In the Altiplano/Puna plateau region internal drainage dates to ~15 Ma and the majority of the topographic uplift has taken place after 10 Ma. Computer models have shown that tectonic deformation is sensitive to internal drainage, because endorheism implies a nearly perfect sediment trap that effectively reduces the output of orogenic erosion to zero. The cancellation of orogen-scale erosion can severely modify tectonic deformation patterns, increase topography and propagate deformation further into the undeformed forelands of the orogenic system. Symmetrically, internal drainage is also promoted by the orographic rain shadow due to the growth of topography in the early stages of tectonism.Numerical models coupling the aforementioned mechanisms have shown that, as sediment transport and accumulation within the endorheic region progresses, the propagation of deformation to areas more distal to the tectonic plate boundary can lead to a lower&#8208;relief landscape. A recent reassessment of the ages of the Tibetan plateau sedimentary record in the Lunpola Basin seems consistent with an early onset of low relief and internal drainage. Finally, as topography and crustal thickness increase, lower crust flow is facilitated by the lower viscosity implied by higher pressure, favoring a further reduction of local relief within the highlands.

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A discussion on the validation of structural interpretations based on the mechanics of sedimentary basins in the northwestern Mediterranean fold-and-thrust belts

BSGF - Earth Sciences Bulletin ◽

10.2113/gssgfbull.187.2.83 ◽

2016 ◽

Vol 187 (2) ◽

pp. 83-104 ◽

Cited By ~ 3

Author(s):

Josselin Berthelon ◽

William Sassi

Keyword(s):

Cross Section ◽

Cross Sections ◽

Numerical Models ◽

Structural Evolution ◽

Sedimentary Basins ◽

Structural Style ◽

Thrust Belts ◽

Fold And Thrust Belts ◽

Thin Skin ◽

Northwestern Mediterranean

Abstract Using the geologist’s interpretation of 6 published balanced cross-sections in the fold and thrust belts of the northwestern Mediterranean, a comparative analysis of the interpreted subsurface structural architecture is used to address the links between the structural style and the mechanics of fold and thrust emplacement. For each cross-section example, the geo-dataset and the methods used by the interpreters are different in quantity and quality. Here we have examined how useful is the content of information of each cross-section to constrain the structural evolution scenario. Each interpretation is examined according to considerations of the mechanics of sedimentary basin deformation and how uncertain is the extrapolation of fault trajectory at depth. It is shown that each case reveals a particular type of structural style: thin-skin or thick skin tectonics, fault-related folding, pre-existing fault pattern. The present structural analysis is used to determine for each cross-section the nature of the mechanical problem to address that will reduce uncertainty on the geologic scenario reconstruction. The proposed mechanical boundary conditions could serve to develop analog or numerical models that aim at testing the mechanical validity of the structural scenario of fold and thrust emplacement.

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